Michael-type addition of phthalimide salts to chiral α,β-unsaturated imides

✍ Scribed by Giuliana Cardillo; Angela De Simone; Luca Gentilucci; Piera Sabatino; Claudia Tomasini

• Book ID: 104214536
• Publisher: Elsevier Science
• Year: 1994
• Tongue: French
• Weight: 384 KB
• Volume: 35
• Category: Article
• ISSN: 0040-4039
• DOI: 10.1016/s0040-4039(00)73317-x

✦ Synopsis

~diChimica"G.cirrmi"rpdC.S~M.-Unksi~%diBdoenr viisdm~2-40126Boktgna-lTALY Recently many cffonts have been focussed on the synthesis of &amino acids as useful intertnedi&s in the lprcparation of biological active compo~nds.~ In this field we have previously qxnted the asymmetic synthesis of &amino acids through 1.4 addition of O-benzylhydroxylamme mediated by Lewis acids on chiral ~~~~-2 In~toddinethebest~~to~a~-~~brm&severalp~&salts~ sczeen&_ We describe here the successful synthesis of (~)-(-)-3-~~~u~ic acid by the 1,4 conjugate addition 3 of phthalimido derivatives to the prochiral o$-unsaturated imides 1 (Scheme 1). Momover the h&haeLlike addition folloti by e1ectrophilic brommation with heuzenesulfonyl bromide results in a highly skfeoselective reaction, useful to iatroduce the two new chiral ccnbncs p&erentially in the lryn c&iguration. The stuwselectivity is controlled by (~~~lJ~e~yl4pheny~~~-2~ as chiml auxiliary.4 (4&s?)-1 (4S,SR,3'R)-2 a: R=H b:R=Me c:R=n-Pk d:R=Pb (4S,5R ,2'S,3'R)-4 scheme 1.